Method for regulating ozone within a washing machine appliance

ABSTRACT

A washing machine appliance and a method for regulating ozone within the same are provided. The method includes activating an ozone generation system of the washing machine appliance in order to initiate a flow of ozonized water into a tub of the washing machine appliance and measuring an amount of ozone within an exhaust conduit of the washing machine appliance with an ozone sensor. Based at least in part on the amount of ozone within the exhaust conduit, various steps can be taken to regulate the amount of ozone within a wash chamber of the washing machine appliance.

FIELD OF THE INVENTION

The present subject matter relates generally to washing machine appliances and methods for regulating ozone within the same.

BACKGROUND OF THE INVENTION

Certain washing machine appliances include ozone generation systems that can assist with sanitizing articles within the washing machine appliances. Such ozone generation systems generally include an ozone generator for generating gaseous ozone. The gaseous ozone is dissolved into water entering a wash chamber of the washing machine appliance in order to generate ozonized water. Such ozonized water can assist with reducing the time and energy required to complete sanitization of articles within the wash chamber relative to thermal sanitation systems. Further, such ozonized water can also assist with reducing biofilm and other microbial growth within the wash chamber.

Generally, ozone generation systems that generate gaseous ozone and inject such gaseous ozone into water to generate ozonized water are expensive. Further, dissolving a suitable or proper amount of gaseous ozone within water can be difficult. Accordingly, a washing machine appliance with an ozone generation system that is relatively cheap to produce would be useful. Also, a washing machine appliance with an ozone generation system that consistently and/or reliably generates ozonized water would be useful.

Monitoring an efficacy of ozone generation systems can also be difficult. In particular, articles within the washing machine appliance's wash chamber are preferably exposed to a particular amount of ozone for a particular amount of time in order to ensure that the articles are suitably sanitized. However, ozone generation systems generally do not include features for monitoring or regulating the amount of ozone in order to ensure effective sanitation of articles. In particular, ozone generation systems generally only monitor the amount of ozone within the wash chamber in order to ensure that the amount of ozone does not exceed regulatory or industry standard limits.

Accordingly, a washing machine appliance with features for regulating ozone within the washing machine appliance would be useful. In particular, a washing machine appliance with features for regulating an amount of ozone within a wash chamber of the washing machine appliance in order to ensure that articles within the wash chamber are suitably sanitized and/or cleaned would be useful.

BRIEF DESCRIPTION OF THE INVENTION

The present subject matter provides a washing machine appliance and a method for regulating ozone within the same. The method includes activating an ozone generation system of the washing machine appliance in order to initiate a flow of ozonized water into a tub of the washing machine appliance and measuring an amount of ozone within an exhaust conduit of the washing machine appliance with an ozone sensor. Based at least in part on the amount of ozone within the exhaust conduit, various steps can be taken to regulate the amount of ozone within a wash chamber of the washing machine appliance. Additional aspects and advantages of the invention will be set forth in part in the following description, or may be apparent from the description, or may be learned through practice of the invention.

In a first exemplary embodiment, a method for regulating ozone within a washing machine appliance is provided. The washing machine appliance has a drum mounted within a tub. The drum defines a wash chamber for receipt of articles for washing. The washing machine appliance has an ozone generation system for directing ozonized water into the tub. The washing machine appliance also has an exhaust conduit for directing gas out of the tub and an ozone sensor for measuring an amount of ozone within the exhaust conduit. The method includes activating the ozone generation system in order to initiate a flow of ozonized water into the tub, measuring the amount of ozone within the exhaust conduit with the ozone sensor, and rotating the drum in order to agitate articles within the wash chamber if the amount of ozone within the exhaust conduit at the step of measuring is greater than a minimum amount of ozone or actuating the ozone generation system in order to initiate an additional flow of ozonized water into the tub if the amount of ozone within the exhaust conduit at the step of measuring is less than the minimum amount of ozone.

In a second exemplary embodiment, a washing machine appliance is provided. The washing machine appliance includes a cabinet and a tub positioned within the cabinet. A drum is rotatably mounted within the drum. The drum defines a chamber for receipt of items for washing. A motor is in mechanical communication with the drum in order to selectively rotate the drum. The washing machine appliance also includes an ozone generation system. The ozone generation system includes a water inlet and a water conduit that extends between the water inlet and the tub. The water conduit is in fluid communication with the water inlet and the tub in order to direct water from the water inlet into the tub. The ozone generation system also includes an ozone generator for supplying ozone to water within water conduit. An exhaust conduit extends between the tub and the cabinet. The exhaust conduit is in fluid communication with tub in order to direct gas out of the tub. An ozone sensor is positioned at the exhaust conduit for measuring an amount of ozone within the exhaust conduit. A controller is in communication with the motor, the water inlet, the ozone generator, and the ozone sensor. The controller is configured for activating the water inlet and the ozone generator in order to initiate a flow of ozonized water through the water conduit, measuring the amount of ozone within the exhaust conduit with the ozone sensor, and rotating the drum with the motor in order to agitate articles within the wash chamber if the amount of ozone within the exhaust conduit at the step of measuring is greater than a minimum amount of ozone or actuating the water inlet and the ozone generator in order to initiate an additional flow of ozonized water through the water conduit if the amount of ozone within the exhaust conduit at the step of measuring is less than the minimum amount of ozone.

In a third exemplary embodiment, a method for regulating ozone within a washing machine appliance is provided. The washing machine appliance has a drum positioned within a tub. The drum defines a wash chamber for receipt of articles for washing. The washing machine appliance has an ozone generation system for directing ozonized water into the tub. The washing machine appliance also has an exhaust conduit for directing gas out of tub and an ozone sensor for measuring an amount of ozone within the exhaust conduit. The method includes initiating a sanitation cycle of the washing machine appliance, activating the ozone generation system in order to initiate a flow of ozonized water into tub, measuring the amount of ozone within the exhaust conduit with the ozone sensor, and directing an additional flow of ozonized water into tub, adjusting a duration of a tumble portion of the sanitation cycle, or draining the tub based at least in part on the amount of ozone within the exhaust conduit of the step of measuring.

These and other features, aspects and advantages of the present invention will become better understood with reference to the following description and appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

A full and enabling disclosure of the present invention, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended figures.

FIG. 1 provides a perspective view of a washing machine appliance according to an exemplary embodiment of the present subject matter.

FIG. 2 provides a schematic view of the exemplary washing machine appliance of FIG. 1.

FIG. 3 provides a schematic view of certain components of the exemplary washing machine appliance of FIG. 1.

FIG. 4 illustrates an exemplary method for operating a washing machine appliance according to an exemplary embodiment of the present subject matter.

FIG. 5 illustrates an exemplary method for regulating ozone within a washing machine appliance according to an exemplary embodiment of the present subject matter.

DETAILED DESCRIPTION

Reference now will be made in detail to embodiments of the invention, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the invention, not limitation of the invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope or spirit of the invention. For instance, features illustrated or described as part of one embodiment can be used with another embodiment to yield a still further embodiment. Thus, it is intended that the present invention covers such modifications and variations as come within the scope of the appended claims and their equivalents.

FIG. 1 illustrates an exemplary washing machine appliance 100. A drum 120 of washing machine appliance 100 rotates about a substantially horizontal axis. Thus, washing machine appliance 100 is generally referred to as a horizontal axis washing machine appliance 100. However, while described in the context of washing machine appliance 100, using the teachings disclosed herein, it will be understood that washing machine appliance 100 is provided by way of example only. Other washing machine appliances having different configurations, different appearances, and/or different features may also be utilized with the present subject matter as well, such as vertical axis washing machine appliances.

Washing machine appliance 100 has a cabinet 102 with a tub 122 mounted therein. Tub 122 is configured for containing wash fluid during operation of washing machine appliance 100. Drum 120 is rotatably mounted within tub 122. Drum 120 extends between a top portion 146 (FIG. 2) and a bottom portion 148 (FIG. 2). Top and bottom portions 146 and 148 of drum 120 are, e.g., vertically, spaced apart from each other. A motor 142 (FIG. 3) is in mechanical communication with drum 120 in order to selectively rotate drum 120 (e.g., during an agitation, a spin, or a tumble cycle of washing machine appliance 100). Drum 120 defines a wash chamber 121 that is configured for receipt of articles for washing. Ribs 126 extend from drum 120 into wash chamber 121. Ribs 126 assist with agitating articles disposed within wash chamber 121 during operation of washing machine appliance 100. For example, ribs 126 may lift articles disposed in drum 120 to top portion 146 of drum 120 during rotation of drum 120 and such articles may subsequently fall to bottom portion 148 of drum 120. Drum 120 also defines a plurality of holes 124. Holes 124 are configured to permit a flow of wash fluid and/or air between wash chamber 121 of drum 120 and tub 122. A detergent drawer 106 is slidably mounted within cabinet 102. Detergent drawer 106 receives detergent and directs the detergent to wash chamber 121 or tub 122 during operation of appliance 100.

Cabinet 102 of washing machine appliance defines an opening 105 that permits user access to wash chamber 121 of drum 120. A door 130 is mounted to cabinet 102 at opening 105 with a hinge 140. A window 136 in door 130 permits viewing of wash chamber 121 during operation of appliance 100. Door 130 also includes a handle 132 that, e.g., a user may pull when opening and closing door 130. Latch 134 is configured for selectively securing door 130 in a closed position.

A control panel 110 with a plurality of input selectors 112 is also mounted to cabinet 102. Control panel 110 and input selectors 112 collectively form a user interface for operator selection of machine cycles and features. A display 114 of control panel 130 indicates selected features, a countdown timer, and/or other items of interest to appliance users.

FIG. 2 provides a schematic view of washing machine appliance 100. As may be seen in FIG. 2, washing machine appliance 100 includes a cold water inlet 150 and a hot water inlet 152. Cold water inlet 150 is in fluid communication with a water source, such as a municipal water main or a well. Thus, cold water inlet 150 is configured for receipt of relatively cold water from the water source. A cold water conduit 154 extends between and fluidly connects cold water inlet 150 and detergent drawer 106. Thus, relatively cold water from cold water inlet 150 can flow through cold water conduit 154 to detergent drawer 106. Conversely, hot water inlet 152 is in fluid communication with a hot water source, such as a hot water heater. Thus, hot water inlet 152 is configured for receipt of relatively hot water from the hot water source. A hot water conduit 156 extends between and fluidly connects hot water inlet 152 and detergent drawer 106. Thus, relatively hot water from hot water inlet 152 can flow through hot water conduit 156 to detergent drawer 106. As will be understood by those skilled in the art and as used herein, the term “water” includes purified water and solutions or mixtures containing water and, e.g., elements (such as calcium, chlorine, and fluorine), salts, bacteria, nitrates, organics, and other chemical compounds or substances.

An inlet conduit 158 extends between and fluidly connects detergent drawer 106 and drum 120 or tub 122. Thus, fluid within detergent drawer 106 can flow through inlet conduit 158 into wash chamber 121 of drum 120 or tub 122. As an example, a user can add a fluid additive, such as detergent, bleach, fabric softener, etc., to detergent drawer 106. Water from cold water inlet 150 and/or hot water inlet 152 can flow into detergent drawer 106 and mix with fluid additive to form a wash fluid. Such wash fluid can flow through inlet conduit 158 into wash chamber 121 of drum 120 or tub 122 in order to assist with cleaning articles disposed within wash chamber 121.

Washing machine appliance 100 also includes a sump 160, e.g., positioned at bottom portion 148 of drum 120 or a bottom portion (not shown) of tub 122 positioned at or proximate bottom portion 148 of drum 120. Liquids within wash chamber 121 can collect within sump 160 during operation of washing machine appliance 100, e.g., due to gravity. A drain conduit 162 is configured for directing liquids out of sump 160. In particular, a drain pump 164 is in configured for urging liquids out of sump 160 through drain conduit 162. Liquids within drain conduit 162 are directed out of washing machine appliance 100, e.g., to a sewer or septic system. In particular, drain pump 164 can urge liquids within sump 160 out of washing machine appliance 100 through drain conduit 162. As an example, drain pump 164 can be activated during a drain cycle of washing machine appliance 100 in order to remove dirty or used wash fluid from sump 160.

An exhaust conduit 166, e.g., positioned at top portion 146 of drum 120 or a top portion (not shown) of tub 122 positioned at or proximate top portion 146 of drum 120, is configured for directed gases, e.g., air, out of wash chamber 121 of drum 120 and/or tub 122. In particular, an air handler or fan 168 is in configured for urging gases out of wash chamber 121 of drum 120 and/or tub 122 through exhaust conduit 166. Gases within exhaust conduit 166 are directed out of washing machine appliance 100, e.g., to an exterior atmosphere. In particular, fan 168 can urge gases within wash chamber 121 of drum 120 and/or tub 122 out of washing machine appliance 100 through exhaust conduit 166. As an example, fan 168 can be activated after a wash cycle of washing machine appliance 100 in order to hinder mildew or mold growth within wash chamber 121 after the wash cycle.

Washing machine appliance 100 also includes an ozone generation system 170. Ozone generation system 170 is configured for injecting ozonized water into wash chamber 121 of drum 120 and/or tub 122. As will be understood by those skilled in the art, such ozonized water can assist with sanitizing or cleaning articles within wash chamber 121 of drum 120.

Ozone generation system 170 includes a water inlet 172. Water inlet 172 is in fluid communication with a water source, such as a municipal water main or a well. Water inlet 172 can be in fluid communication with the same water source as cold water inlet 150 or any other suitable water source. Water inlet 172 is configured for receipt of water from the water source. A water conduit 174 extends between and fluidly connects water inlet 172 and sump 160. Thus, water from water inlet 172 can flow through water conduit 174 to sump 160. In alternative exemplary embodiments, water conduit 174 can extend between and fluidly connects water inlet 172 and wash chamber 121 of drum 120 and/or tub 122. Thus, water conduit 174 can direct water from water inlet 172 into wash chamber 121 of drum 120 and/or tub 122.

Ozone generation system 170 also includes a water softener 176 disposed within washing machine appliance 100 downstream of water inlet 172. Water softener 176 can assist with removal of minerals, such as calcium, magnesium, etc., from water flowing through water conduit 174. Water softener 176 can be any suitable mechanism for softening water flowing through water conduit 174. For example, water softener 176 may rely on reverse osmosis or ion-exchange polymers.

An ozone generator 178 is also positioned within washing machine appliance 100 downstream of water inlet 172. Ozone generator 178 is configured for generating ozone within water in water conduit 174 and/or otherwise directing ozone into such water. Thus, when ozone generator 178 is active, water within water conduit 174 downstream of ozone generator 178 contains ozone and is ozonized water. Ozone generator 178 can be any suitable device for generating ozonized water within water conduit 174. For example, ozone generator 178 may be an electrolytic ozone cell, a corona discharge unit, or an ultraviolet unit. In particular, ozone generator 178 may be a plurality of electrolytic ozone cells connected to each other in series.

Ozone generation system 170 includes an ozone sensor 180 positioned on or within exhaust conduit 166. Ozone sensor 180 is configured for measuring an amount of ozone within exhaust conduit 166. In alternative exemplary embodiments, ozone sensor 180 can be positioned at any other suitable location. For example, ozone sensor 180 may be positioned within wash chamber 121 of drum 120 and/or tub 122 for measuring the amount of ozone within wash chamber 121.

A catalyst 182 is also positioned within exhaust conduit 166. Catalyst 182 is configured for reducing the amount of ozone within exhaust conduit 166. Catalyst 182 can be any suitable device for reducing and/or destroying ozone within exhaust conduit 166. For example, catalyst 182 may be monometallic and include a precious metal such as palladium or bimetallic in the form of an oxide with different valence states or in a zero valence metallic state.

FIG. 3 provides a schematic view of certain components of washing machine appliance 100. As may be seen in FIG. 3, washing machine appliance 100 includes a processing device or controller 144. Operation of washing machine appliance 100 is controlled by controller 144.

Controller 144 includes memory and one or more processing devices such as microprocessors, CPUs or the like, such as general or special purpose microprocessors operable to execute programming instructions or micro-control code associated with operation of washing machine appliance 100. The memory can represent random access memory such as DRAM, or read only memory such as ROM or FLASH. The processor executes programming instructions stored in the memory. The memory can be a separate component from the processor or can be included onboard within the processor. Alternatively, controller 144 may be constructed without using a microprocessor, e.g., using a combination of discrete analog and/or digital logic circuitry (such as switches, amplifiers, integrators, comparators, flip-flops, AND gates, and the like) to perform control functionality instead of relying upon software.

Controller 144 is operatively coupled to various components of washing machine appliance 100. For example, washing machine appliance 100 includes control panel 110 for user manipulation to select washing machine cycles and features. Controller 144 is in communication with control panel 110. Thus, in response to user manipulation of control panel 110, controller 144 operates the various components of washing machine appliance 100 to execute selected machine cycles and features.

As an example, a user can load articles for washing into wash chamber 121, and the user can initiate washing operation through manipulation of input selectors 112 of control panel 110. Controller 144 then actuates cold water inlet 150 and/or hot water inlet 152 in order to fill drum 120 and/or tub 122 with water and/or detergent to form a wash fluid in the manner discussed above. Once drum 120 and/or tub 122 is properly filled with wash fluid, controller 144 activates motor 142 in order to agitate the articles within wash chamber 121 with ribs 126 and assist with cleansing such articles.

After the agitation phase of the wash cycle is completed, controller 144 activates drain pump 164 to remove wash fluid from drum 120 and/or tub 122. Articles can then be rinsed by adding relatively clean fluid to drum 120 and/or tub 122, depending on the particulars of the cleaning cycle selected by a user, ribs 126 may again provide agitation within wash chamber 121. One or more spin cycles may also be used. In particular, a spin cycle may be applied after the wash cycle and/or after the rinse cycle in order to wring wash fluid from the articles being washed. During a spin cycle, drum 120 is rotated at relatively high speeds.

During a sanitation cycle of washing machine appliance 100, controller 144 can activate ozone generation system 100 to direct ozonized water into sump 160. Thus, controller 144 is in operative communication with various components of ozone generation system 170, including water inlet 172, ozone generator 178, and ozone sensor 180. Thus, controller 144 can actuate water inlet 172 in order to direct water into water conduit 174. Further, controller 144 can activate ozone generator 178 in order to generate ozone within water within water conduit 174 or direct ozone into water within water conduit 174.

To monitor the amount of ozone within wash chamber 121 of drum 120 and/or tub 122, controller 144 can receive a signal from ozone sensor 180. The signal from ozone sensor 180 corresponds to the amount of zone within exhaust conduit 166. In turn, the amount of ozone within exhaust conduit 166 can be correlated to the amount of ozone within wash chamber 121 and the amount of ozone within liquids therein. As discussed in greater detail below, utilizing measurements from ozone sensor 180, controller 144 can monitor the amount of ozone in order to ensure efficacy of ozonized water within wash chamber 121.

FIG. 4 illustrates an exemplary method 400 for operating a washing machine appliance according to an exemplary embodiment of the present subject matter. Method 400 can be utilized to regulate an amount of ozone within washing machine appliance 100 (FIG. 1). Controller 144 of washing machine appliance 100 can be programmed to implement method 400. Method 400 can assist with ensuring sufficient ozone is within liquids in wash chamber 121 or tub 122 to sanitize articles within wash chamber 121.

At step 410, controller 144 initiates a sanitation or rinse cycle of washing machine appliance 100. During the rinse cycle, articles within wash chamber 121 are rinsed with relatively clean liquid in order to remove detergent and other fluid additives from the articles. In addition, as discussed in greater detail below, ozonized water can assist with sanitizing and cleaning articles within wash chamber 121 during the rinse cycle. During the rinse cycle, controller 144 can operate or activate fan 168 in order to draw gases from wash chamber 121 into exhaust conduit 166. Thus, fan 168 can assist ozone sensor 180 with measuring ozone within wash chamber 121 by pulling air from wash chamber 121 into exhaust conduit 166.

At step 415, controller 144 receives a signal from ozone sensor 180. The signal from ozone sensor 180 corresponds to a measurement of an amount of ozone within exhaust conduit 166. From the measurement of the amount of ozone within exhaust conduit 166, controller 144 can determine an amount of ozone within liquid in wash chamber 121. For example, the amount of ozone within exhaust conduit 166 can be directly proportional to the amount of ozone within liquid in wash chamber 121. At step 415, wash chamber 121 generally has little or no ozone located therein. Thus, the measurement from ozone sensor 180 at step 415 can correspond to a baseline measurement for ozone sensor 180.

At step 420, controller 144 activates ozone generation system 170 in order to direct ozonized water into wash chamber 121 and/or sump 160. Thus, controller 144 can activate water inlet 172 and ozone generator 178 at step 420 in order to direct ozonized water into sump 160. Such ozonized water can be used to sanitize and/or clean articles within wash chamber 121 during the rinse cycle.

At step 425, controller 144 measures the amount of ozone within exhaust conduit 166 with ozone sensor 180. Wash chamber 121 at step 425 generally has more ozone therein relative to wash chamber 121 at step 415 due to ozonized water directed into wash chamber 121 at step 420.

At step 430, controller 144 compares the measured amount of ozone within exhaust conduit 166 from step 425 to a minimum amount of ozone. The minimum amount of ozone can correspond to an amount of ozone required to sanitize articles within wash chamber 121 of drum 120. Thus, at step 430, controller 144 can ensure that sufficient ozone is within wash chamber 121 to properly sanitize and/or clean articles within wash chamber 121. For example, if the measured amount of ozone within exhaust conduit 166 from step 425 is less than the minimum amount, the amount of ozone within wash chamber 121 is not sufficient to properly sanitizing and/or clean articles within wash chamber 121. Conversely, the amount of ozone within wash chamber 121 is sufficient to properly sanitize and/or clean articles within wash chamber 121 if the measured amount of ozone within exhaust conduit 166 from step 425 is equal to or greater than the minimum amount.

At step 435, controller 144 rotates drum 120 with motor 142 if the amount of ozone within exhaust conduit 166 at step 425 is greater than the minimum amount of ozone. Thus, controller 144 activates motor 142 to rotate drum 120 and tumble or agitate articles located within wash chamber 121 if the amount of ozone within wash chamber 121 is sufficient to properly sanitizing and/or clean articles within wash chamber 121. By rotating drum 120 and tumbling or agitating articles located within wash chamber 121, ozonized water can be dispersed throughout articles, and such ozonized water can assist with sanitizing and cleaning articles. Thus, controller 144 can rotate drum 120 with motor 142 at step 435 for a period of time sufficient for ozonized water to sanitize and/or clean articles within wash chamber 121.

At step 440, controller 144 obtains another measurement of the amount of ozone within exhaust conduit 166 with ozone sensor 180. In particular, controller 144 obtains another measurement of the amount of ozone within exhaust conduit 166, after motor 142 has tumbled articles within drum 120 for the period of time discussed above. Wash chamber 121 at step 440 generally has more ozone therein relative to wash chamber 121 at step 425, e.g., due to tumbling of articles in drum 120 at step 435 that can release gaseous ozone from ozonized water in wash chamber 121.

At step 445, controller 144 compares the measured amount of ozone within exhaust conduit 166 from step 440 to a maximum amount of ozone. The maximum amount of ozone can correspond to a limit on the amount of ozone permitted by regulation or industry standards, such as UL2157. Thus, at step 445, controller 144 can ensure that the amount of ozone within wash chamber 121 does not exceed, e.g., safety, limits. For example, if the measured amount of ozone within exhaust conduit 166 from step 445 is less than the maximum amount, the amount of ozone within wash chamber 121 is within regulatory or industry standard limits. If the measured amount of ozone within exhaust conduit 166 from step 445 exceeds the maximum level, controller 144 can activate motor 142 to spin drum 120 as at step 435.

At step 450, controller 144 activates or turns on drain pump 164 in order to drain wash chamber 121 of drum 120 and/or tub 122. Thus, drain pump 164 removes ozonized water from drum 120 and/or tub 122 at step 450 via drain conduit 162. Controller 144 can also activate motor 142 at step 450 in order to spin drum at a relatively high speed in order to wring liquids or extract wash fluids from articles within wash chamber 121. Controller 144 activates drain pump 164 and motor 142 at step 450 if the amount of ozone within exhaust conduit 166 at step 445 is less than the maximum amount of ozone. Thus, after articles within wash chamber 121 are sanitized and/or cleaned with ozonized water at step 435, controller 144 can activate drain pump 164 to remove such ozonized water from the articles and drum 120 and/or tub 122.

Steps 435, 440, 445, and 450 correspond to a normal operating procedure for washing machine appliance 100 during the rinse cycle. However, as discussed above, insufficient ozone can be present within wash chamber 121 to properly sanitize and/or clean articles within wash chamber 121 at step 430. Thus, method 400 includes steps for ensuring that rinse cycle is effective and that sufficient ozone is present within wash chamber 121 to properly sanitize and/or clean articles within wash chamber 121 during the rinse cycle. Such steps are discussed in greater detail below.

At step 455, controller 144 reactivates ozone generation system 170 in order to direct ozonized water into wash chamber 121 and/or sump 160 if the amount of ozone within exhaust conduit 166 at step 430 is less than the minimum amount of ozone. Thus, controller 144 can activate water inlet 172 and ozone generator 178 at step 455 in order to direct additional ozonized water into sump 160. Such additional ozonized water can be used to sanitize and/or clean articles within wash chamber 121 during the rinse cycle. Further, such additional ozonized water can increase the amount of ozone within wash chamber 121. Thus, if the amount of ozone within exhaust conduit 166 at step 430 is less than the minimum amount of ozone, additional ozonized water is directed into wash chamber 121 and/or sump 160.

At step 460, controller 144 obtains another measurement of the amount of ozone within exhaust conduit 166 with ozone sensor 180. In particular, controller 144 obtains another measurement of the amount of ozone within exhaust conduit 166 after ozone generation system 170 directs additional ozonized water into wash chamber 121 and/or sump 160 at step 455.

At step 465, controller 144 compares the measured amount of ozone within exhaust conduit 166 from step 460 to the minimum amount of ozone. Thus, at step 465, controller 144 can ensure that sufficient ozone is within wash chamber 121 to properly sanitize and/or clean articles within wash chamber 121. Thus, after directing additional ozonized water into wash chamber 121 at step 455, controller 144 can determine whether the additional ozonized water is sufficient to sanitize and/or clean articles within wash chamber 121.

At step 470, controller 144 activates or turns on drain pump 164 in order to drain drum 120, sump 160, and/or tub 122 of liquid if the amount of ozone within exhaust conduit 166 at step 465 is less than the minimum amount of ozone. Thus, if after adding additional ozonized water to wash chamber 121 the amount of ozone within exhaust conduit 166 at step 465 is still less than the minimum level then drum 120 and/or tub 122 can be drained and, e.g., controller 144 can restart the rinse cycle.

At step 475, controller 144 spins drum 120 with motor 142 if the amount of ozone within exhaust conduit 166 at step 460 is greater than the minimum amount of ozone. Thus, controller 144 activates motor 142 to rotate drum 120 and tumble or agitate articles located within wash chamber 121 if the amount of ozone within wash chamber 121 is sufficient to properly sanitize and/or clean articles within wash chamber 121 after adding additional ozonized water at step 455. By rotating drum 120 and tumbling or agitating articles located within wash chamber 121, ozonized water can be dispersed throughout articles, and such ozonized water can assist with sanitizing and cleaning articles. Thus, controller 144 can spin drum 120 with motor 142 at step 475 for a period of time sufficient for ozonized water to sanitize and/or clean articles within wash chamber 121.

At step 480, controller 144 receives an additional measurement of the amount of ozone within exhaust conduit 166 with ozone sensor 180. In particular, controller 144 obtains the additional measurement of the amount of ozone within exhaust conduit 166, after motor 142 has tumbled articles within drum 120 for the period of time. Wash chamber 121 at step 480 generally has more ozone therein relative to wash chamber 121 at step 460, e.g., due to tumbling of articles in drum 120 at step 475 that can release gaseous ozone from ozonized water in wash chamber 121.

At step 485, controller 144 compares the measured amount of ozone within exhaust conduit 166 from step 480 to the maximum amount of ozone. Thus, at step 445, controller 144 can ensure that the amount of ozone within wash chamber 121 does not exceed, e.g., safety, limits. If the measured amount of ozone within exhaust conduit 166 from step 485 exceeds the maximum level, controller 144 can activate motor 142 to revolve drum 120 as at step 475.

At step 490, controller 144 activates or turns on drain pump 164 in order to drain wash chamber 121 of drum 120 and/or tub 122. Thus, drain pump 164 removes ozonized water from drum 120 and/or tub 122 at step 490 via drain conduit 162. Controller 144 can also activate motor 142 at step 490 in order to spin drum at a relatively high speed in order to wring liquids or extract wash fluids from articles within wash chamber 121. Controller 144 activates drain pump 164 and motor 142 at step 490 if the amount of ozone within exhaust conduit 166 at step 445 is less than the maximum amount of ozone. Thus, after articles within wash chamber 121 are sanitized and/or cleaned with ozonized water at step 475, controller 144 can activate drain pump 164 to remove such ozonized water from the articles and drum 120 and/or tub 122.

Method 400 described above assists with regulating the amount of ozone within washing machine appliance 100, e.g., within wash chamber 121. In particular, method 400 can ensure that the rinse cycle of washing machine appliance 100 provides sufficient ozone to articles within wash chamber 121 to properly sanitize and/or clean articles within wash chamber 121.

FIG. 5 illustrates an exemplary method 500 for regulating ozone within a washing machine appliance according to an exemplary embodiment of the present subject matter. Method 500 can be utilized to regulate an amount of ozone within washing machine appliance 100 (FIG. 1). Controller 144 of washing machine appliance 100 can be programmed to implement method 400. Method 500 can assist with ensuring sufficient ozone is within liquids in wash chamber 121 or tub 122 to sanitize articles within wash chamber 121.

At step 510, controller 144 initiates a sanitation or rinse cycle of washing machine appliance 100. During the rinse cycle, articles within wash chamber 121 are rinsed with relatively clean liquid in order to remove detergent and other fluid additives from the articles. In addition, as discussed in greater detail below, ozonized water can assist with sanitizing and cleaning articles within wash chamber 121 during the rinse cycle. During the rinse cycle, controller 144 can operate or activate fan 168 in order to draw gases from wash chamber 121 into exhaust conduit 166. Thus, fan 168 can assist ozone sensor 180 with measuring ozone within wash chamber 121 by pulling air from wash chamber 121 into exhaust conduit 166.

At step 520, controller 144 activates ozone generation system 170 in order to direct a flow of ozonized water into wash chamber 121 and/or sump 160. Thus, controller 144 can activate water inlet 172 and ozone generator 178 at step 520 in order to direct ozonized water into sump 160. Such ozonized water can be used to sanitize and/or clean articles within wash chamber 121 during the rinse cycle.

At step 530, controller 144 receives a signal from ozone sensor 180. The signal from ozone sensor 180 corresponds to a measurement of an amount of ozone within exhaust conduit 166. From the measurement of the amount of ozone within exhaust conduit 166, controller 144 can determine an amount of ozone within liquid in wash chamber 121. For example, the amount of ozone within exhaust conduit 166 can be directly proportional to the amount of ozone within liquid in wash chamber 121.

At step 540, controller 144 activates ozone generation system 170 in order to direct an additional flow of ozonized water into wash chamber 121 of drum 120 and/or tub 122, selectively activates motor 142 in order to adjust a duration of a tumble or agitation portion of the rinse cycle, or activates drain pump 164 in order to drain wash chamber 121 of drum 120 and/or tub 122 based at least in part on the amount of ozone within exhaust conduit 166 at step 530. For example, controller 144 can activate ozone generation system 170 at step 540 if the amount of ozone within exhaust conduit 166 at step 530 is less than a minimum amount of ozone required to properly sanitize and/or clean articles within wash chamber 121. Similarly, controller 144 can selectively activate motor 142 at step 540 if the amount of ozone within exhaust conduit 166 at step 530 is more than a minimum amount of ozone required to properly sanitize and/or clean articles within wash chamber 121. Further, controller 144 can activate drain pump 164 at step 540 if the amount of ozone within exhaust conduit 166 at step 530 less than a minimum amount of ozone required to properly sanitize and/or clean articles within wash chamber 121.

It should be understood that washing machine appliance 100 need not include catalyst 182 to destroy ozone within washing machine appliance 100. In alternative exemplary embodiments, washing machine appliance 100 can utilize any other suitable mechanism for destroying or reducing ozone within washing machine appliance 100. For example, washing machine appliance 100 can rely upon natural decay of ozone to reduce the amount of ozone within washing machine appliance 100.

This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they include structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims. 

What is claimed is:
 1. A method for regulating ozone within a washing machine appliance, the washing machine appliance having a drum positioned within a tub, the drum defining a wash chamber for receipt of articles for washing and an ozone generation system for directing ozonized water into tub, the washing machine appliance also having an exhaust conduit for directing gas out of the tub and an ozone sensor for measuring an amount of ozone within the exhaust conduit, the method comprising: activating the ozone generation system in order to initiate a flow of ozonized water into the tub of the washing machine appliance; measuring the amount of ozone within the exhaust conduit with the ozone sensor; rotating the drum in order to agitate articles within the wash chamber if the amount of ozone within the exhaust conduit at the step of measuring is greater than a minimum amount of ozone or actuating the ozone generation system in order to initiate an additional flow of ozonized water into tub of the washing machine appliance if the amount of ozone within the exhaust conduit at the step of measuring is less than the minimum amount of ozone.
 2. The method of claim 1, wherein the minimum amount of ozone corresponds to an amount of ozone required to sanitize articles within the wash chamber of the drum.
 3. The method of claim 1, further comprising: obtaining another measurement of the amount of ozone within the exhaust conduit with the ozone sensor after the step of rotating; and spinning the drum in order to agitate articles within the wash chamber if the amount of ozone within the exhaust conduit at the step of obtaining is greater than a maximum amount of ozone or draining the tub of the washing machine appliance if the amount of ozone within the exhaust conduit at the step of obtaining is less than the maximum amount of ozone.
 4. The method of claim 3, further comprising revolving the drum after the step of draining in order to extract wash fluid from articles within the wash chamber.
 5. The method of claim 1, further comprising: obtaining another measurement of the amount of ozone within the exhaust conduit with the ozone sensor after the step of actuating; and spinning the drum in order to agitate articles within the wash chamber if the amount of ozone within the exhaust conduit at the step of obtaining is greater than the minimum amount of ozone or draining the tub of the washing machine appliance if the amount of ozone within the exhaust conduit at the step of obtaining is less than the minimum amount of ozone.
 6. The method of claim 5, further comprising: receiving an additional measurement of the amount of ozone within the exhaust conduit with the ozone sensor after the step of spinning; and revolving the drum in order to agitate articles within the wash chamber if the amount of ozone within the exhaust conduit at the step of receiving is greater than a maximum amount of ozone or draining the tub of the washing machine appliance if the amount of ozone within the exhaust conduit at the step of receiving is less than the maximum amount of ozone.
 7. A washing machine appliance, comprising: a cabinet; a tub positioned within the cabinet; a drum rotatably mounted within the tub, the drum defining a chamber for receipt of items for washing; a motor in mechanical communication with the drum in order to selectively rotate the drum; an ozone generation system comprising a water inlet; a water conduit extending between the water inlet and the tub, the water conduit being in fluid communication with the water inlet and the tub in order to direct water from the water inlet into the tub; and an ozone generator for supplying ozone to water within water conduit; an exhaust conduit extending between the tub and the cabinet, the exhaust conduit being in fluid communication with the tub in order to direct gas out of the tub; an ozone sensor positioned at the exhaust conduit for measuring an amount of ozone within the exhaust conduit; and a controller in communication with the motor, the water inlet, the ozone generator, and the ozone sensor, the controller configured for activating the water inlet and the ozone generator in order to initiate a flow of ozonized water through the water conduit; measuring the amount of ozone within the exhaust conduit with the ozone sensor; and rotating the drum with the motor in order to agitate articles within the wash chamber if the amount of ozone within the exhaust conduit at the step of measuring is greater than a minimum amount of ozone or actuating the water inlet and the ozone generator in order to initiate an additional flow of ozonized water through the water conduit if the amount of ozone within the exhaust conduit at the step of measuring is less than the minimum amount of ozone.
 8. The washing machine appliance of claim 7, wherein the minimum amount of ozone corresponds to an amount of ozone required to sanitize articles within the chamber of the drum.
 9. The washing machine appliance of claim 7, wherein the controller is further configured for: obtaining another measurement of the amount of ozone within the exhaust conduit with the ozone sensor after the step of rotating; and spinning the drum with the motor in order to agitate articles within the wash chamber if the amount of ozone within the exhaust conduit at the step of obtaining is greater than a maximum amount of ozone or draining the tub if the amount of ozone within the exhaust conduit at the step of obtaining is less than the maximum amount of ozone.
 10. The washing machine appliance of claim 7, wherein the controller is further configured for: obtaining another measurement of the amount of ozone within the exhaust conduit with the ozone sensor after the step of actuating; and spinning the drum with the motor in order to agitate articles within the wash chamber if the amount of ozone within the exhaust conduit at the step of obtaining is greater than the minimum amount of ozone or draining the tub if the amount of ozone within the exhaust conduit at the step of obtaining is less than the minimum amount of ozone.
 11. The washing machine appliance of claim 10, wherein the controller is further configured for: receiving an additional measurement of the amount of ozone within the exhaust conduit with the ozone sensor after the step of spinning; and revolving the drum with the motor in order to agitate articles within the wash chamber if the amount of ozone within the exhaust conduit at the step of receiving is greater than a maximum amount of ozone or draining the tub if the amount of ozone within the exhaust conduit at the step of receiving is less than the maximum amount of ozone.
 12. The washing machine appliance of claim 7, further comprising a sump positioned proximate a bottom portion of the drum, the sump being in fluid communication with tub, the water conduit extending between the water inlet and the sump in order to direct water from the water inlet into the sump.
 13. The washing machine appliance of claim 7, wherein the ozone generator comprises at least one electrolytic ozone cell.
 14. The washing machine appliance of claim 7, further comprising a fan positioned within the exhaust conduit, the fan configured for urging gases from the tub into the exhaust conduit.
 15. The washing machine appliance of claim 14, further comprising a catalyst positioned within the exhaust conduit downstream of the ozone sensor, the catalyst configured for reducing the amount of ozone within the exhaust conduit.
 16. The washing machine appliance of claim 7, further comprising: a detergent drawer in fluid communication with the tub; a cold water inlet; a cold water conduit extending between the cold water inlet and the detergent drawer, the cold water conduit being in fluid communication with the cold water inlet and the detergent drawer in order to direct water from the cold water inlet into the detergent drawer; a hot water inlet; and a hot water conduit extending between the hot water inlet and detergent drawer, the hot water conduit being in fluid communication with the hot water inlet and the detergent drawer in order to direct water from the hot water inlet into the detergent drawer.
 17. The washing machine appliance of claim 7, wherein the exhaust conduit is positioned proximate a top portion of the drum.
 18. A method for regulating ozone within a washing machine appliance, the washing machine appliance having a drum mounted within a tub, the drum defining a wash chamber for receipt of articles for washing, the washing machine appliance having an ozone generation system for directing ozonized water into tub, the washing machine appliance also having an exhaust conduit for directing gas out of tub and an ozone sensor for measuring an amount of ozone within the exhaust conduit, the method comprising: initiating a sanitation cycle of the washing machine appliance; activating the ozone generation system in order to initiate a flow of ozonized water into the tub; measuring the amount of ozone within the exhaust conduit with the ozone sensor; and directing an additional flow of ozonized water into tub, adjusting a duration of a tumble portion of the sanitation cycle, or draining the tub based at least in part on the amount of ozone within the exhaust conduit of the step of measuring. 